Join National Geographic Explorer Zeb Hogan on a quest to save some of the biggest freshwater fish in the world. We'll track the elusive freshwater stingray, believed to be only a legend in northern Cambodia until Hogan came face to face with one. Need proof? See exclusive, never-before-seen underwater images of these giant freshwater stingrays. Then, Hogan is off to Southeast Asia to study the giant Mekong catfish, which can grow to be as large as a grizzly bear! Today more than 70 percent of the giant Mekong catfish are in danger of extinction due to overfishing and rapid development along the great rivers of Asia. Using underwater tracking devices to locate their mysterious spawning grounds, he attempts to unravel the mystery of where these titans of the deep live and breed. Then, witness a rare capture of a giant Mekong and watch Hogan persuade local fishermen to release the endangered creature back into the wild.

National Geographic magazine's Top 10 Photos of the Year presents a countdown to the magazines best image from 2009, chosen by National Geographic magazine editor in chief Chris Johns from his list of the 10 best photographs published in the magazine last.

Six 800-year-old skeletons have been discovered at a crusader castle in Jordan. For hundreds of years, only legends could hint at how these men possibly members of the Knights Templar met their fate while battling a Muslim army. Now, though rigorous forensic investigation, Warrior Graveyard examines every stab wound, sword slash and arrow strike to reveal telltale signs of horrific violence, including dismemberment, bludgeoning and even ritual execution.

Each year in the Australian outback, the dry season leaves five top predators- giant stingrays, sawfish, bull sharks, and freshwater and saltwater crocodiles- stranded in waterholes with limited food supplies. Zeb sets out to find out how each of the giants has adapted to the environment and which one is the ultimate king of the pool. With the help of local experts, Zeb gets up close with a bull shark's sharp teeth, wades through knee-deep water in the dark of night searching for a stingray.

The world didn't end on 5/21/11 as some feared, but someday it will, and not just on Earth, but for asteroids, comets, moons, planets, stars and everything in our Known Universe. To demonstrate this complex cycle of life and death, scientist David Kaplan watches the destruction of a 16-story building shattering the structure while creating new matter and debris. We'll also see how a wildfire compares to the ignition of a supernova deep in space, and step inside a black hole simulator.

Over the centuries, explorers traded tales of a lost civilization amid the dense Amazonian rainforest. Scientists dismissed the legends as exaggerations, believing that the rainforest could not sustain such a huge population – until now. A new generation of explorers armed with 21st-century technology has uncovered remarkable evidence that could reinvent our understanding of the Amazon and the indigenous peoples who lived there.

The psychological effects of war are no longer considered just a human condition. Africa is cultivating gangs of juvenile delinquents, wreaking havoc in the wild. African elephants are becoming edgy 30 years of poaching and conservation management is beginning to backfire, resulting in abnormal violent behavior. In Kenya, elephants are targeting and killing the Maasai tribes cattle. In South Africa, 36 rhinos are killed in a single park over a period of two years. And in Western Uganda a village is being subjected to indiscriminate and violent attacks by local elephants - where, previously they had roamed peacefully.